Parsing skin effect in a non-Hermitian spinless BHZ-like model

Dipendu Halder; Saurabh Basu

doi:10.1088/1361-648x/ad4940

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arXiv · 2304.12723

Parsing skin effect in a non-Hermitian spinless BHZ-like model

Dipendu Halder·Saurabh Basu

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Abstract

This work comprehensively investigates the non-Hermitian skin effect (NHSE) in a spinless Bernevig- Hughes-Zhang (BHZ)-like model in one dimension. It is generally believed that a system with non-reciprocal hopping amplitudes demonstrates NHSE. However, we show that there are exceptions, and more in-depth analyses are required to decode the presence of NHSE or its variants in a system. The fascinating aspects of our findings, depending on the inclusion of non-reciprocity in the inter-orbital hopping terms, concede the existence of conventional NHSE or NHSE at both edges and even a surprising absence of NHSE. The topological properties and the (bi-orthogonal) bulk-boundary correspondence, enumerated via computation of the (complex) Berry phase and spatial localization of the edge modes, highlight the topological phase transitions occurring therein. Further, to facilitate a structured discussion of the non-Hermitian model, we split the results into PT symmetric and non-PT symmetric cases with a view to comparing the two.

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Dipendu Halder, Saurabh Basu. 2024-05-09. Parsing skin effect in a non-Hermitian spinless BHZ-like model. https://doi.org/10.1088/1361-648x%2Fad4940

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